summaryrefslogtreecommitdiff
path: root/libdde_linux26/contrib/include/linux/virtio.h
diff options
context:
space:
mode:
authorZheng Da <zhengda1936@gmail.com>2009-12-06 05:26:23 +0100
committerZheng Da <zhengda1936@gmail.com>2009-12-06 05:26:23 +0100
commit8a6d48c0542876eb3acfc0970c0ab7872db08d5f (patch)
tree496e78bc728317ea779781b92f897d16936ee231 /libdde_linux26/contrib/include/linux/virtio.h
parentb4bffcfcdf3ab7a55d664e9aa5907f88da503f38 (diff)
check in the original version of dde linux26.
Diffstat (limited to 'libdde_linux26/contrib/include/linux/virtio.h')
-rw-r--r--libdde_linux26/contrib/include/linux/virtio.h120
1 files changed, 120 insertions, 0 deletions
diff --git a/libdde_linux26/contrib/include/linux/virtio.h b/libdde_linux26/contrib/include/linux/virtio.h
new file mode 100644
index 00000000..06005fa9
--- /dev/null
+++ b/libdde_linux26/contrib/include/linux/virtio.h
@@ -0,0 +1,120 @@
+#ifndef _LINUX_VIRTIO_H
+#define _LINUX_VIRTIO_H
+/* Everything a virtio driver needs to work with any particular virtio
+ * implementation. */
+#include <linux/types.h>
+#include <linux/scatterlist.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+
+/**
+ * virtqueue - a queue to register buffers for sending or receiving.
+ * @callback: the function to call when buffers are consumed (can be NULL).
+ * @vdev: the virtio device this queue was created for.
+ * @vq_ops: the operations for this virtqueue (see below).
+ * @priv: a pointer for the virtqueue implementation to use.
+ */
+struct virtqueue
+{
+ void (*callback)(struct virtqueue *vq);
+ struct virtio_device *vdev;
+ struct virtqueue_ops *vq_ops;
+ void *priv;
+};
+
+/**
+ * virtqueue_ops - operations for virtqueue abstraction layer
+ * @add_buf: expose buffer to other end
+ * vq: the struct virtqueue we're talking about.
+ * sg: the description of the buffer(s).
+ * out_num: the number of sg readable by other side
+ * in_num: the number of sg which are writable (after readable ones)
+ * data: the token identifying the buffer.
+ * Returns 0 or an error.
+ * @kick: update after add_buf
+ * vq: the struct virtqueue
+ * After one or more add_buf calls, invoke this to kick the other side.
+ * @get_buf: get the next used buffer
+ * vq: the struct virtqueue we're talking about.
+ * len: the length written into the buffer
+ * Returns NULL or the "data" token handed to add_buf.
+ * @disable_cb: disable callbacks
+ * vq: the struct virtqueue we're talking about.
+ * Note that this is not necessarily synchronous, hence unreliable and only
+ * useful as an optimization.
+ * @enable_cb: restart callbacks after disable_cb.
+ * vq: the struct virtqueue we're talking about.
+ * This re-enables callbacks; it returns "false" if there are pending
+ * buffers in the queue, to detect a possible race between the driver
+ * checking for more work, and enabling callbacks.
+ *
+ * Locking rules are straightforward: the driver is responsible for
+ * locking. No two operations may be invoked simultaneously, with the exception
+ * of @disable_cb.
+ *
+ * All operations can be called in any context.
+ */
+struct virtqueue_ops {
+ int (*add_buf)(struct virtqueue *vq,
+ struct scatterlist sg[],
+ unsigned int out_num,
+ unsigned int in_num,
+ void *data);
+
+ void (*kick)(struct virtqueue *vq);
+
+ void *(*get_buf)(struct virtqueue *vq, unsigned int *len);
+
+ void (*disable_cb)(struct virtqueue *vq);
+ bool (*enable_cb)(struct virtqueue *vq);
+};
+
+/**
+ * virtio_device - representation of a device using virtio
+ * @index: unique position on the virtio bus
+ * @dev: underlying device.
+ * @id: the device type identification (used to match it with a driver).
+ * @config: the configuration ops for this device.
+ * @features: the features supported by both driver and device.
+ * @priv: private pointer for the driver's use.
+ */
+struct virtio_device
+{
+ int index;
+ struct device dev;
+ struct virtio_device_id id;
+ struct virtio_config_ops *config;
+ /* Note that this is a Linux set_bit-style bitmap. */
+ unsigned long features[1];
+ void *priv;
+};
+
+int register_virtio_device(struct virtio_device *dev);
+void unregister_virtio_device(struct virtio_device *dev);
+
+/**
+ * virtio_driver - operations for a virtio I/O driver
+ * @driver: underlying device driver (populate name and owner).
+ * @id_table: the ids serviced by this driver.
+ * @feature_table: an array of feature numbers supported by this device.
+ * @feature_table_size: number of entries in the feature table array.
+ * @probe: the function to call when a device is found. Returns a token for
+ * remove, or PTR_ERR().
+ * @remove: the function when a device is removed.
+ * @config_changed: optional function to call when the device configuration
+ * changes; may be called in interrupt context.
+ */
+struct virtio_driver {
+ struct device_driver driver;
+ const struct virtio_device_id *id_table;
+ const unsigned int *feature_table;
+ unsigned int feature_table_size;
+ int (*probe)(struct virtio_device *dev);
+ void (*remove)(struct virtio_device *dev);
+ void (*config_changed)(struct virtio_device *dev);
+};
+
+int register_virtio_driver(struct virtio_driver *drv);
+void unregister_virtio_driver(struct virtio_driver *drv);
+#endif /* _LINUX_VIRTIO_H */